<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>四级联动</title>
</head>
<body>
	<select>
		<option>省</option>
	</select>
	<select>
		<option>市</option>
	</select>
	<select>
		<option>区</option>
	</select>
	<select>
		<option>街道</option>
	</select>
</body>
</html>